Structural stability analysis of naturally ventilated polyhouses under different conditions

This research work on structural stability analysis of naturally ventilated polyhouses was carried out at the Department of Soil and Water Engineering, Punjab Agricultural University, Ludhiana. There were 12 treatments which were combination of four different sizes of polyhouses i.e. 560 (T1-T3); 1,008 (T4-T6); 2,080 (T7-T9); 4,000 m2 (T10-T12), with three design wind speeds of 100, 150, and 200 km h-1, respectively. Stability analysis of truss members, columns, and foundation was carried out by considering dead loads, live loads and wind loads. Support reactions were computed on truss and column joints. Member forces were computed by using force method.  For every 17 set of truss members, four members [two in compression (small arc) and two in tension (truss bracings)] failed in treatments with 150 and 200 km h-1 wind speed, while in treatments with 100 km h-1 wind speed, two members [in compression, (small arc)] failed. Minimum structural GI pipe material requirement for structurally stable polyhouses was under treatment T1 (2,407 kg) and the maximum was under treatment T12 (19,550 kg).